Some automobile interior parts are finished with matte coating. A coating material blended with particles (for example, a coating material blended with inorganic particles such as silica and talc, or resin particles such as acrylic resin particles, urethane resin particles, nylon resin particles, silicone resin particles and polyethylene resin particles) is used for such matte coating finishing. A coating film obtained from the coating material blended with such particles can cause the particles existing on the surface to moderately diffuse and reflect incident light and to reduce the gross.
Incidentally, hardness of the particles affects a touch feeling and scratchability of the coating film obtained from the coating material blended with the particles. For example, inorganic particles such as silica and talc are hard, and the coating film obtained from the coating material blended with such hard particles has a hard touch feeling and is easily scratched when impact is applied thereto from the outside. On the other hand, the resin particles are softer than the inorganic particles, and the coating film obtained from the coating material blended with such soft particles has a soft touch feeling (soft feel properties) and high elasticity, and is hardly scratched when impact is applied thereto from the outside.
Accordingly, in recent years, soft resin particles that can provide an excellent scratch resistance to a coating film are being developed.
For example, soft resin particles with a low compression strength, specifically, with a compression strength at the time of 10% compression deformation in the range of 0.01 to 0.6 kgf/mm2 (0.1 MPa to 5.88 MPa) are disclosed in Patent Documents 1 to 5.